Electric fuel pump - fuel lines LEAKS

[boardmonkey]

There isn't usually a 'spare' terminal on the back of an alternator have you attached it to the terminal that is intended for a suppressor? 11.9v is a pretty flat battery and no output from the alternator.

Yeah I took the reading after cranking the engine and getting nothing...now I have just ran the test when the engine is running....

Both batteries read 12.2v
Turn Engine on
battery behind passenger seat reads 13.20
Other battery behind drivers seat reads 13.74

So if the Alternator is pushing a charge through then its working ok is it not ?

Thanks, Richard

[Oldiebut goodie]

12.2v isn't a sign of very healthy batteries, most of us have uprated our alternator voltage regulator to a 14.5v one, it looks as though yours is the old 13.8v type. I prefer to see 12.7/12.8v for a fully charged battery after it has been left for a while after charging, I should think that most on here would be the same.

[CovKid]

Alternator light has to go out before pump will get power - if thats the way you wired it.

Uprated alternator regulator is one way, the other is better cables. I did the latter and get a good charge to both batteries now.

[ghost123uk]

So reading what CovKid just wrote, has the pump been wired to the "blue" wire that feeds the ign light and the split charge relay? (rhetorical Q I think, for Richard’s benefit). If "Yes" then CovKid is of course correct as that wire only becomes properly "live" once the alternator has tripped in (often needs a blip of over 2,000 rpm to trip some of them).

[marlinowner]

Best to wire the pump with a switchover relay as described by bigherb in separate thread, maybe with a separate switch so you can test pump / prime carb manually.

[ghost123uk]

^^^

[boardmonkey]

Best to wire the pump with a switchover relay as described by bigherb in separate thread, maybe with a separate switch so you can test pump / prime carb manually.

I did wire in to a relay, exactly as Big Herb stated, but not with a separate switch for priming manually. The vans started fine late last night and again this morning. However which one is the alternator light, is it the battery on the dash as that stays on. The temp light flashes then goes out.

Going to remove both batteries and give them a good charge, see how they are after this...

Alternator - mine is the Bosch Green 45A 025 903 023 A type, so looking at getting a replacement alternator regulator for the time being.

Thanks for all the useful comments.

[ghost123uk]

However which one is the alternator light, is it the battery on the dash as that stays on.

A bit confusing here, unless you have a problem that is. Yes the "alternator" light is also called the "battery charging light", on the dash. But, it should go off as soon as you start the engine. It goes off to indicate the battery is charging correctly. If it stays on, either your alternator, or it's wiring, is not charging the battery up. Or, you have upset the balance of that warning circuit by connecting your fuel pump to it's wiring, which from what I have read sounds possible, even likely, because =

power for the fule pump from the back of the alternator theres a spare temrinal to a 10A fuse and then onto the relay.

Though I think I read earlier on that the relay can be powered from that warning light circuit, (for safety, ie fuel pump stops when the engine stops) much as the split charge relay is. It does seem though that your warning circuit is not behaving correctly. Perhaps the relay you are using for the fuel pump is pulling too much current and upsetting it. (that circuit is not designed for much current).

Whatever the cause, that light on the dash should go out when the motor is running. Note that some alternators require a bit of a rev up to "kick them in".

[CovKid]

Could be. The pump itself only draws 2 amps.

[marlinowner]

I guess you could use one of the smart split charge relays to power the pump from the main alternator output.

[ghost123uk]

But then the pump would not fire up until the motor was running and the alternator had kicked in, which is OK when there is fuel in the float chamber, but no good if there ain't. Then you would need a manual (non locking) "primer" switch for the pump (which I believe CovKid has). Talking of which, was it CovKid (or someone else?) who did a write up on the best way to power an electric fuel pump? (I had a quick look in the wiki but didn't find one)

[marlinowner]

Yes, but using a switchover relay which also drives the pump from the starter trigger so the pump runs when starting. Bigherbs circuit from other thread but with the pump relay coil powered through smart split charge relay rather than alternator warning light circuit.

[ghost123uk]

Ah, got ya

[boardmonkey]

Hi,

The battery light did go out this time after Id revved it, so thats all groovy...

Next post....oil leak. I dont think my van wants to go away for Easter....

[CovKid]

I have to do the same but got so used to it, its not a problem now. Once I feel I'm not likely to get rheumatism working on it, I'll rewire is so its not dependent on the alternator. Its a rather simple solution and works, but not ideal.